Stateless pigmies lived in the handful of scruffy villages lining the 20-miles of no mans land between Congo and Cameroon. I was muddy and shirtless when I rounded a corner and unexpectedly arrived at the makeshift hut housing the immigration office. It looked like a makeshift slum house but an immaculately dressed guard stepped out and started shouting at me. His furious French was to the tune of: How dare you arrive here in such an indecent state. What if there had been women here. Go away and put a shirt on.I wheeled my bike back around the corner to dress. While doing so I spotted two village women emerge from the bushes with water containers. They wandered off down the track; topless like me.

The Chinese shopkeeper served his Chinese customer who walked outside, climbed into his Chinese car and drove away on the Chinese built road - presumably to his job on one of the numerous Chinese construction projects in the area. The Republic of Congo was proving to be quite different to how I had expected. To be fair, it was formerly known as "The People's Republic of Congo" so China's interest could be idealogical. However, I suspect that the large, timber-rich country of only 4 million people has other attractions for savvy eastern investors.

The sound of the Lulua river - a constant companion for many days - faded behind us. We'd spent three weeks navigating rapids and fretting about crocodiles or hippos tipping our old dugout our canoe but a vast field of waterfalls and churning white water had finally proved to intimidating for us and our leaking craft. We'd have to finish our crossing or the Congo by land.

Each carrying bags, Archie and I followed the two men wheeling our bicycles along the tight, jungle footpath. We ducked low branches and our clothes snagged on the thorns that sprouted rudely from just about every plant. We'd offered our pirogue (dugout canoe) to the small village of Lulua tribespeople in exchange for help portering kit. Two young boys with bamboo fishing rods walked behind us bearing our paddles (now downgraded in status from 'useful' to 'souvenir'). Their quiet chatter was accompanied by the soothing ambience of bird calls, falling leaves and distantly snapping twigs.

We were headed for a track on which we'd be able to cycle to a road and thence to a town. Having been forced to quit the river unexpectedly and maplessly, unsure where we even were, we felt a little like we'd been airdropped in the Congo with old bicycles and tasked with finding a way out. The accumulated exhaustion of the challenges we had faced on the river lapped at our still-standing bodies. Like a tide, it threatened to rear up and force us into involuntary rest before we reached an appropriate place.

The water had become too fast, and the rocks too many. We hadn't been prepared for this; hadn't had a chance to stop and scout ahead by foot. Having finally fought our way free of a narrow, overgrown channel of quick water running through dense forest, our lumbering dugout canoe suddenly surged out into the open. Archie and I, already exhausted, looked ahead in panic.

We were speeding towards a churning field of rapids. Boulders littered the wide waterway and each one threatened to undo us. We managed a couple of risky and unplanned 360 degree pirouettes between obstacles before the breaks became too high and we inevitably struck a rock. Water gushed over the sides and, in a desperate attempt to avoid the pirogue sinking, we leapt overboard. The fierce current dragged us unsympathetically over shallow rocks to the end of the rapids. The pirogue's nose had gone under and the rear was only held near the surface by the empty water containers we used as buoyancy aids. Our bags floated off in various directions while we desperately thrashed back and forth in the still-speeding water, shepherding them to the moving 'base' of our sinking canoe.

Archie and I sat on a hillside wasteland by the town of Sandoa and shared an almost-cold Simba beer. The river Lulua lay before us; only 40m wide and invitingly placid. The dying light of dusk reflected silver on this winding swathe of water that lumbered in the valley bottom. This was the river we'd spotted on a map, half a year earlier when tipsy in Cape Town, and vaguely vowed to descend by pirogue (the traditional, flat-bottomed dugout canoe, ubiquitous across Congo). The mosquitos rose and we retreated to the Salvatorian Catholic mission where we were renting a couple of guest rooms. We'd found our river, now we needed to find our pirogue.

The dense eyebrows of the minister danced furiously in accompaniment to the rapid-fire mixture of French and Swahili that spat from his mouth. Sweat poured from his wide, bald pate - and from the bodies of the 1,000-strong congregation folded into the 20x20m "Église Evangéliqué" in Lubumbashi, Democratic Republic of Congo.

Archie and I had been walking down a narrow back alley when we heard what sounded like a lively rally. We followed our ears towards the chanting and found the simple church (iron girders, breeze blocks and corrugated metal roof) with a woman lying in the dirt by the open door...retching. We slipped past and joined the fracas of faith within.